Drill.



B. KUNlTZn DRILL.

APPLICATION FILED JULY 28, 1914.

Patented May 25, 1915.

BENJAMIN KUNITZ,

00., Inc, or BROOKLYN,

OF NEW YORK,-N. Y-, ASSIGNOR TO AMERICAN PLASTERFDRILL NEWfYOBK, ACORPORATION OF NEW YORK.

DRILL.

To all whom itmay concern .Improvements in Drills,

Be it known that I, BENJAMIN Kpisrrz, a subject; of the Czar of Russia,residing at I New York, in the county of Kings'and State.

of New York, have invented new and useful of whichthe following is aspecification.

This invention relates to drill bits and it consists in the novelfeatures hereinafter described and claimed.

An object of the invention is to provide a drill bit especially adaptedto be used by electricians when installing electric wires in buildings.These wires are generally passed through iron or metal pipes and at thepoint where the wires enter the room of a building the wall or ceilingis provided with a socket to receive the outlet box. The bit which formsthe subject matter of this invention is especially adapted to be usedfor cutting the said socket in the wall for the reception of the box andthis can be done notwithstanding the presence of the pipe in the wall atthe point where the socket is to 'be cut.

WVith the above object in view the bit includes a tubular shank having ahead applied to one end thereof and a basin mounted thereon adapted tocatch the chips or dust which fall from the wall or ceiling during thecutting operation. A stud having a screw may be inserted in the head ora sleeve may be inserted in the head in lieu of said stud. Radiallydisposed cutting blades are mounted upon the head and are adapted toremove the material from the wall when the shank is rotated. I

In the accompanying drawing: Figure 1 is a side elevation of the drillbit with parts in section. Fig. 2 is an end elevation of the same withparts removed. Fig. 3 is a transverse sectional view of the bit out onthe line 3-3 of Fig. 2.. Fig. 4 is a detailed sectional view of portionsof the bit out on the line 4.-1 of Fig. 2. Fig. 5 is a perspective Viewof one of the blades of the bit. Fig. 6 is a perspective view of asleeve which may be used in the bit.

The bit includes a shank 1 which is preferably tubular and which may beconnected in any suitable means with an ordinary brace. A sleeve 2 isadjustably mounted upon the shank 1 and is held at an adjusted positionby means of a set screw 3. A basin 4 is mounted .upon the sleeve 2 andarms 5 Specification of Letters Patent. t t May 25, 1915, Applicationfiled July as, 1914.. Serial No. 853,754.

extend from one end. of the sleeve 2 to the intermediate portion of thebasin 4 and brace the same in its position upon the sleeve. A head 6 isscrew threaded upon one end of the shank 1 and is held in position bymeans of a jam nut 7 also screw threaded-upon the said shank and whichbears at one side against one end of the head 6. The head 6 is providedwith a central opening 8 and also with a set screw 9 which passestransversely through one side of the head 6. A stud 10 may be insertedin the opening 8 of the head 6 and secured therein by tightening the setscrew 9. The stud 10' is provided with a screw extremity 11 which mayenter the wall when the bit is in use and the stud 10 is employed in thebit. A blade holder 12 is mounted upon the head 6 and is provided withrecesses 13 which receive the shanks 14 of blades 15. The blades 15 areprovided with cutting edges 16 which against the outer edges of theshanks 11 of the blades 15 and serve as means for holding the saidblades in position upon the blade holder 12. hen the parts are arrangedas shown in Fig. 1 of the drawing and it is desired to cut a hole in aceiling, the operator stands under the point at which the hole is to becut and by rotating the shank 1 the screw 11 is caused to enter theceiling and eventually the cutting edges 16 of the blades encounter theceiling and accomplish the cutting thereof. The chips or material whichis removed from the ceiling fallsinto the basin 1 and consequently thismaterial does not fall into the eyes of the operator nor does it fall.upon the floor below. When it is desired to form a socket about a pipein a ceiling or wall the stud 10 is removed and the sleeve 19 isinserted in the opening 8 and secured therein by using the set screw 9.The sleeve 19 receives the end of the pipe and by rotating the shank 1the cutting edges 16 of the blades 15 will cut the socket in the ceilingor wall around the pipe and in the socket the outlet box hereinafterreferred to may be inserted. Therefore it will be seen that a drill bitof simple and durable structure is provided as shown in Fig. 2 of thedrawing are sub and that the'bit may be easily and readily transformedfrom one intended to be used for ordinary drilling purposes into oneespecially adapted to be used for cutting a opening, a blade supportmountedupon the head and provided with recesses, blades having shankslocated in the recesses and provided with cutting edges, plates mountedupon the blade holders and clamping against the shanks of the blades anda guiding member detachably mounted in the opening in the head. 2. Adrill bit comprising a shank, a hea mounted thereon and having anopening, a blade-holder mounted upon the head, blades carried by theblade holder, plates mounted upon'the blade holder and clamped againstthe blades, and a sleeve detachably mounted in the opening in the headand means for holding the sleeve in position in the head.

In testimony whereof I afiix my signa-- ture in presenceof twowitnesses.

BENJAMIN KUNITZ. Witnesses:

JOHN A. DONEGAN, 'Gno. A. BYRNE.

